About

Solar Cell

DYE-SENSITIZED SOLAR CELLA solar cell is a photonic device that converts photons with specific wavelengths to electricity. A dye-sensitized solar cell (DSSC) is a low-cost solar cell belonging to the group of thin film solar cells. It is based on a semiconductor formed between a photo-sensitized anode and an electrolyte, a photoelectrochemical system. The modern version of a dye solar cell, also known as the Grätzel cell, was originally co-invented in 1988 by Brian O'Regan and Michael Grätzel. In general, a DSC comprises a nanocrystalline titanium dioxide (TiO2) electrode modified with a dye fabricated on a transparent conducting oxide (TCO), a platinum (Pt) counter electrode, and an electrolyte solution with a dissolved iodide ion/triiodide ion redox couple between the electrodes.

Even though the conversion efficiency of dye-sensitized cells is lower than that of some other thin-film cells, their price to performance ratio is sufficient to make them an important player in the solar market. The advantages of DSSCs are listed below: * They are the most efficient third-generation solar technology available, absorbing more sunlight per surface area than standard silicon-based solar panels. * DSSCs are an attractive replacement for current technologies in low density applications such as rooftop solar collectors, where the light weight and mechanical robustness of the printable cell is a key benefit. * These may not be as attractive for large-scale deployments where high-efficiency, high-cost cells are more suitable. However, even minimal future increases in the conversion efficiency of the DSSC may make it suitable for some of these applications. * DSSCs work even in low-light conditions such as non-direct sunlight and cloudy skies. * They are economical, easy to manufacture and constructed from abundant and stable resource materials. * The mechanical robustness of the DSSC leads indirectly to higher efficiencies at a range of temperatures. * Normally, DSSCs are built with just a thin conductive plastic top layer, helping heat to be radiated away more easily and hence operate at low internal temperatures. Construction

In the case of the original Grätzel and O'Regan design, the cell has 3 primary parts. On top is a transparent anode made of fluoride-doped tin dioxide (SnO2:F) deposited on the back of a (typically glass) plate. On the back of this conductive plate is a thin layer of titanium dioxide (TiO2), which forms into a highly porous structure with an extremely high surface area. TiO2 only absorbs a small fraction of the solar photons (those in the UV). The plate is then immersed in a mixture of a photosensitive ruthenium-polypyridine dye (also called molecular sensitizers) and a solvent. After soaking the film in the dye solution, a thin layer of the dye is left covalently bonded to the surface of the TiO2. A separate plate is then made with a thin layer of the iodide electrolyte spread over a conductive sheet, typically platinum metal. The two plates are then joined and sealed together to prevent the electrolyte from leaking. The construction is simple enough that there are hobby kits available to hand-construct them. Although they use a number of "advanced" materials, these are inexpensive compared to the silicon needed for normal cells because they require no expensive manufacturing steps. TiO2, for instance, is already widely used as a paint base. Operation

Sunlight enters the cell through the transparent SnO2:F top contact, striking the dye on the surface of the TiO2. Photons striking the dye with enough energy to be absorbed create an excited state of the dye, from which an electron can be "injected" directly into the conduction band of the TiO2. From there it moves by diffusion (as a result of an electron concentration gradient) to the clear anode on top. Meanwhile, the dye molecule has lost an electron and the molecule will decompose if another electron is not...

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...DEGRADATION OF MULTICRYSTALLINE SOLARCELL IN SHIPPING PROCESS
Chia-Cheng Chou*1), Der-Ray Huang*1)
*1Dept. of Opto-Electronic Engineering, National Dong Hwa University
Abstract
This study described the deterioration by performance of power, variance of surface and quantum efficiency (QE) in multicrystalline silicon solarcell (mc-Si solarcell) after vibration test which was simulated under the condition of land & air transportation. The vibration test follows some procedures from an unpublished draft of one developing international Standard. Mechanical defects on the surface of solarcell were obviously inspected by recognizable patterns evolving, shown from the method of electroluminescence (EL) imaging. The patterns were classified into 7 types by symptoms of crack/micro-crack. On the other hand, quantum efficiency variances of cell were measured in incident photon-to-electron conversion efficiency (IPCE), i.e. IPCE performance drop was found indeed in spectrum as 23.7%. After vibration test, total breakage rate is near 1% and some specific cells had 3% power loss in I-V measurement. EL images showed the sufficient evidences of defect’s growth due to mc-Si cells experienced vibration response during transshipment simulation. Furthermore, this applied research provided a common vibration test from a...

...SolarCell Practical Report 2011
Aim: To find the amount of power generated from a solarcell with a light bulb by using a multimeter.
Hypothesis: The further you move the solarcell away from the light bulb the less power will be produced.
Backup statement: I can support my hypothesis through my own given knowledge on power and electricity. I can comprehend the facts that, if the Light Bulb was generating a large amount of heat and light, the solar panel would be absorbing a majority of this energy if it were to be extremely close to the light bulb. Yet if the solar panel was to be drawn away, it would slowly lose that energy due to the distance of the panel.
Variables:
-Dependant: Power output
-Independent: Distance of solarcell
-Consistent Variables: the electricity of the light bulb, solarcell, voltage, amps
Materials:
• Ruler
• Multimeter
• Solar panel (cell)
• Light bulb
• Pencil/pen
• Paper
• Alligator clips
Method:
1. Set up the equipment by plugging in the Light Bulb and attaching the Solar Panel to the Multimeter with the Alligator clips and the wires.
2. Begin by using a ruler to measure out the required distances for the practical
3. Switch on your multimeter and turn the switch clockwise until...

...A solarcell (also called photovoltaic cell or photoelectric cell) is a solid state electrical device that converts the energy of light directly into electricity by the photovoltaic effect.
Assemblies of cells used to make solar modules which are used to capture energy from sunlight, are known as solar panels. The energy generated from these solar modules, referred to as solar power, is an example of solar energy.
Photovoltaics is the field of technology and research related to the practical application of photovoltaic cells in producing electricity from light, though it is often used specifically to refer to the generation of electricity from sunlight.
Cells are described as photovoltaic cells when the light source is not necessarily sunlight. These are used for detecting light or other electromagnetic radiation near the visible range, for example infrared detectors, or measurement of light intensity.
History of solarcells
Main article: Timeline of solarcells
The term "photovoltaic" comes from the Greek φῶς (phōs) meaning "light", and "voltaic", from the name of the Italian physicist Volta, after whom a unit of electro-motive force, the volt, is named. The term "photo-voltaic" has been in use in English since...

...Photosynthesis vs. Semiconductor based solarcell.
Photosynthesis vs. Semiconductor based solarcell.
Wais Ghowsi
Instructor: Meri Stanec
SCI 115
April 24th, 2011
What is Photosynthesis?
Photosynthesis simply means the conversion of light energy into chemical energy by living organisms. In photosynthesis, the raw materials are water and carbon dioxide. Energy is taken from sunlight and the end products give out glucose and oxygen. It is the most important, naturally occurring process of life because all living organisms depend on it. In this process, plants use solar energy to produce sugar. then during cellular respiration, these sugars are converted into ATP. ATP is the fuel that is used by all living organisms. The conversion of the unused sunlight energy into usable chemical energy is associated with the actions of the green pigment chlorophyll. In this process, water is used and oxygen is released that we absolutely need to stay alive. we can write the over all reaction of this process as:
6 Water molecule’s + 6 CO2 molecule’s + light → 1 Glucose molecule + 6 oxygen molecule’s
How is solar energy transformed into electrical energy?
Solar energy is what keeps us all alive. The earths temperature is retained from the light and heat taken from the sun. how easily solar energy is converted into light energy is important. The Photovoltaic...

...A Review of Laser Processes Used in SolarCell Fabrication
Abstract
There are many different laser techniques that can be used in the production of solarcells. By examining the research which the various solarcells were fabricated with laser technique, it is possible to understand the pros and cons of using laser for produce the cells. The following paragraphs will list which process the laser technique have been used in this review.
Introduction
The buried contact solarcell was invented at University of New South Wales by Green et al. in 1983. These solarcells have a relatively high efficiency approximately 25% and present a possibility of cost-reduction with applying this technology to the manufacturers’ production lines.
The following are the general main steps of forming the buried contact solarcell:
1. Texturing of surfaces
2. Top surface diffusion
3. Oxide growth
4. Groove cutting and diffusion
5. Aluminum deposition and sinter
6. Metal plating
7. Edge isolation
The key parts of this process, which result in the cells become more efficiency than the standard screen printing solarcells are the laser grooving and groove diffusion to reduce the cell shading and contact resistance and the...

... and electricity is being generated and passed through the red wires at the end4.
Generating electricity through light comes about from exciting the electrons in a material when light is applied to it. The light displaces electrons in the material, most commonly a p-n junction semiconductor, which then leaves ‘free holes’ that allow electrons from other atoms to move into it. This resultant movement gives rise to electricity. The term photovoltaic comes from the Greek word ‘phos’ meaning light and ‘voltaic’ meaning electric. The materials presently used for photovoltaic’s include monocrystalline silicon, polycrystalline silicon, cadmium telluride and copper indium selenide/sulfide6. This is an example of a common use of solar/ photovoltaic cells.
Uses of Piezoelectricity
Some common uses of piezoelectricity include;
Quartz crystals in watches
Cigarette lighters
X-ray shutters
Inkjet printers.
The Boeing 777 uses piezoelectric ceramic material within its ultrasonic fuel tank probes. The ultrasonic transducers are installed at a variety of locations in each fuel tank. A pulsed electric field is applied to the material, which then responds by oscillating. The resulting sound waves are reflected off the surface of the fuel and picked up by the transducer. A digital signal processor interprets the ‘time of flight’ measurement of the sound waves in order to continually indicate the amount of fuel present 2....

...Photovoltaic cells are solid state devices that convert light directly into electricity. Photovoltaic literally means "light electricity." These devices can be commonly found providing power for small scale devices such as calculators, watches, and small radios. However, they are not limited to small scale systems. They are also used to power satellites, communications equipment, houses and many other things, especially in remote locations where a power grid is not readily available. In isolated locations the only power attainable comes from the sun. The sun shines approximately 1000 watts of energy per square meter of the planets surface, which if harnessed could power any city.
The commercial development of the photovoltaic cell took more then a hundred years to begin. A french physicist Edmond Becquerel first described the photovoltaic effect in 1839. At the age of 19 Becquerel found that certain materials when exposed to light produced small measurable currents. Henrich Hertz also studied the effect in solids in the 1870's and he managed to produce photoelectric cells with an efficiency of about 1%. In the 1940's the new Czochralski process made generating highly pure crystalline silicon possible and furthermore made commercializing photovoltaic cells an option. Development really started however, in 1954 when Bell Laboratories used the Czochralski process to produce a 4% efficient crystalline silicon...